don't use mapMonotonic in domain in case there are duplicate entries
don't use mapMonotonic in domain in case there are duplicate entries

darcs-hash:20060425051757-1a7c6-e37c78ca83de73d655cde7928185f2545f19c1c1

jimcrayne/jhc,jimcrayne/jhc,jimcrayne/jhc,jimcrayne/jhc